So, you don't have GPS capability. It's not the end of the world.
You are OBSESSING over this. I want to clarify the whole "you only get one shot at this," since I'm pretty sure that came from me.
When I say this, I'm referring more to the MINDSET of confrontation/exposure, and the overall STRATEGY, more than I am to any specific list of TACTICS, or even their order. When I see others blow it, they do things like:
- reveal the source of their intel;
- get too specific with what they know, instead of saying "I know all about... ," thereby giving the cheating spouse the opportunity to spin the specifics;
- go all "melty man" at the first bone the cheating spouse throws them;
- are not patient in gathering their intel and building their plan, and instead confront incrementally, with shaky evidence, that sounds more like half-baked accusations than the "shock-and-awe" confront-and-expose it's meant to be;
- don't have their legal ducks in a row;
- don't have their financial ducks in a row;
- aren't prepared with what their consequences are going to be; what is the "or else" part of the boundary-laying;
- generally come off as more begging and pleading and accusatory, than as a calm, confident, STRONG leader.
Those are my normal concerns. If you've got those covered (and I think you do), then don't sweat the small stuff (timing, etc.). You can make small tactical errors and still be OK! Remember:
There is power in her not knowing what you know, and what you DON'T know, and if you convey the "I know all about" speech and DON'T let her drag you into giving specifics of what you know or the source(s) of your intel . . . then she will have to assume YOU KNOW EVERYTHING, and she'll have to play her cards accordingly.